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991.
Gaurang Pant Prakaipetch Punchaipetch M. J. Kim Robert M. Wallace Bruce E. Gnade 《Thin solid films》2004,460(1-2):242-246
Physical and electrical properties of hafnium silicon oxynitride (HfSixOyNz) dielectric films prepared by UV ozone oxidation of hafnium silicon nitride (HfSiN) followed by annealing to 450 °C are reported. Interfacial layer growth was minimized through room temperature deposition and subsequent ultraviolet/ozone oxidation. The capacitance–voltage (C–V) and current–voltage (I–V) characteristics of the as-deposited and annealed HfSixOyNz are presented. These 4 nm thick films have a dielectric constant of 8–9 with 12 at.% Hf composition, with a leakage current density of 3×10−5 A/cm2 at Vfb+1 V. The films have a breakdown field strength >10 MV/cm. 相似文献
992.
Solution of a Well-Field Design Problem with Implicit Filtering 总被引:1,自引:0,他引:1
Fowler Kathleen R. Kelley Carl T. Miller Cass T. Kees Christopher E. Darwin Robert W. Reese Jill P. Farthing Matthew W. Reed Mark S. C. 《Optimization and Engineering》2004,5(2):207-234
Problems involving the management of groundwater resources occur routinely, and management decisions based upon optimization approaches offer the potential to save substantial amounts of money. However, this class of application is notoriously difficult to solve due to non-convex objective functions with multiple local minima and both nonlinear models and nonlinear constraints. We solve a subset of community test problems from this application field using MODFLOW, a standard groundwater flow model, and IFFCO, an implicit filtering algorithm that was designed to solve problems similar to those of focus in this work. While sampling methods have received only scant attention in the groundwater optimization literature, we show encouraging results that suggest they are deserving of more widespread consideration for this class of problems. In keeping with our objectives for the community problems, we have packaged the approaches used in this work to facilitate additional work on these problems by others and the application of implicit filtering to other problems in this field. We provide the data for our formulation and solution on the web. 相似文献
993.
A study, comparing the effect of blowing agent selection on energy consumption and the life cycle climate performance (LCCP) of a typical European refrigerator is discussed. Energy consumption of prototype European-style refrigerators made with a foam formulation with HFC-245fa as the blowing agent was measured and compared with energy consumption of the same model as currently produced (using a foam with a pentane blend for the blowing agent). Results were used in a LCCP study, considering both direct and indirect climate impacts due to blowing agent emissions and energy consumption in manufacturing processes and over the life cycle of the refrigerator. An assumption is made that the refrigerator is built and used in the European market. 相似文献
994.
This paper addresses the problem of frazil ingestion by submerged water intakes located offshore in frigid water. It is well known that intakes under such conditions are prone to blockage by frazil, small ice crystals that commonly occur when water, agitated by wind or current, supercools. However, little quantitative information exists delineating how intake shape and size influence intake ingestion of frazil ice. Presented herein are insights and quantitative trends associated with those influences. The insights and trends were obtained from observations of frazil in a set of unique ice-tank experiments of a common intake configuration. The experiments were extended through numerical simulation. The essential intake layout considered herein comprises a conical inlet connected by pipe to an onshore pump station, and fitted with an elevated cap. The study’s findings show how either a cap or larger intake-rim diameter reduce the rate of frazil ingestion. Reducing the rate of frazil ingestion may enable an intake to operate longer during periods of water supercooling, and thereby reduce the possibility of blockage by frazil. 相似文献
995.
Vierck Charles J. Jr.; Kline Robert IV; Wiley Ronald G. 《Canadian Metallurgical Quarterly》2004,118(3):627
In behavioral tests, rats performed learned escape responses to thermal stimulation of the paws by 44.0. 47.0. or 0.3 degrees C. Licking, guarding, and jumping reflexes were evaluated at these temperatures. The frequency, latency, and duration of escape and reflex responses were compared and were related to hind-paw skin temperatures measured during stimulation of awake and anesthetized rats. The duration and latency of escape from heat were appropriately related to stimulus intensity. Escape occurred reliably for each intensity. Reflexes occurred unreliably and at long latency to 44.0 or 0.3 degrees C and were not appropriately related to heat intensity. The reflexes were relatively insensitive to thermal nociceptive stimulation other than heating of the skin at a high rate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
The purpose of the current study was to examine in detail the association between witnessing domestic violence (DV) and long-term psychological adjustment. Important limitations of past research were addressed, including controlling for several associated risk factors. Special attention was paid to whether the perpetrator of the violence was the maternal or paternal figure, as well as to whether the witness to the violence was male or female. Participants completed measures examining DV witnessed, direct child abuse experienced, and current psychopathology. Following screening for physical and sexual abuse, a sample of 351 individuals was selected. Four groups of participants were compared. Results indicated that individuals who had witnessed either physical DV or major psychological DV had higher levels of psychopathology than individuals who reported witnessing minor psychological DV or controls. After controlling for direct psychological abuse experienced, witnessing DV remained a significant predictor of psychopathology for males but not for females. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Forgiveness and Conflict Resolution in Marriage. 总被引:1,自引:0,他引:1
Two studies examined whether forgiveness in married couples is associated with better conflict resolution. Study 1 examined couples in their 3rd year of marriage and identified 2 forgiveness dimensions (retaliation and benevolence). Husbands' retaliatory motivation was a significant predictor of poorer wife-reported conflict resolution, whereas wives' benevolence motivation predicted husbands' reports of better conflict resolution. Examining longer term marriages, Study 2 identified three forgiveness dimensions (retaliation, avoidance and benevolence). Whereas wives' benevolence again predicted better conflict resolution, husbands' avoidance predicted wives' reports of poorer conflict resolution. All findings were independent of both spouses' marital satisfaction. The findings are discussed in terms of the importance of forgiveness for marital conflict and its implications for spouse goals. Future research directions on forgiveness are outlined. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Zakowski Sandra G.; Ramati Alona; Morton Carla; Johnson Peter; Flanigan Robert 《Canadian Metallurgical Quarterly》2004,23(6):555
The aims of the present study were to examine whether written emotional disclosure would reduce distress among cancer patients and whether it would buffer the effects of high levels of social constraint (negative social responses to patients' expressions of emotion regarding their cancer) on distress. Cancer patients (N=104) were randomly assigned to write about their emotions regarding their cancer 20 min a day for 3 days or to write about a nonemotional topic. They completed questionnaires at baseline and 6 months postintervention. Results showed that written disclosure buffered the effects of social constraints on stress at the 6-month follow-up and that avoidance partly mediated these effects. The present data reinforce the notion that interventions should be tailored to patients' needs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Sadek Joseph R.; Johnson Shannon A.; White Desirée A.; Salmon David P.; Taylor Kirsten I.; DeLaPena Jody H.; Paulsen Jane S.; Heaton Robert K.; Grant Igor 《Canadian Metallurgical Quarterly》2004,18(4):692
Remote memory was assessed in persons with HIV-associated dementia (HIV-D), probable Alzheimer's disease (AD), and Huntington's disease (HD) and in healthy controls. The clinical groups were similar in overall dementia severity. Each clinical group exhibited impairments on remote memory tests relative to controls; however, temporally graded memory loss with selective preservation of older information was observed in the AD group but not the HD or HIV-D group. Analysis of cued retrieval indicated a preferential cuing benefit for the HIV-D and HD groups relative to the AD group. The similar pattern of remote memory performance demonstrated by the HIV-D and HD groups is a novel finding and suggests a subcortically mediated retrograde amnesia in HIV-D. The temporally graded pattern and the abnormal cued retrieval performance in the AD group are consistent with a consolidation deficit associated with extrahippocampal (cortical) and hippocampal damage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Dingfang Liu John J. Sansalone Frank K. Cartledge 《Canadian Metallurgical Quarterly》2004,130(4):383-390
Divalent metal species adsorption onto a manganese oxide coated polymeric medium (MOPM) was evaluated through batch adsorption experiments using a flow-through batch reactor. In this paper, Part II, the batch equilibrium and kinetic data examined in Part I are modeled using a triple layer surface complexation model and a potential driving second order kinetic model. Surface complexation modeling using FITEQL-TLM generated intrinsic surface acidity constants for the MOPM of log?K?a1int = 3.196 and log?K?a2int = ?5.802. The intrinsic surface reaction constants for Pb(II), Cu(II), and Zn(II) were log?K?Pbint = ?1.91, log?K?Cuint = ?2.53, and log?K?Znint = ?4.45, respectively. A potential driving second order kinetic model was developed to predict sorption of the divalent metal ions onto the MOPM. The general adsorption kinetics for MOPM can be described as a fast reaction occurring within 30 min and a slower reaction continuing from 5 to 15 h. Kinetic results can be interpreted using assumptions of the potential driving second order model that the dominant control forces are the chemical potential of the MOPM activated surface sites and chemical potential of sorbate in the solution. 相似文献